1. Field of the Invention
The present invention pertains to systems for measuring multiphase fluid flow, particularly mixtures of oil, water and gas, by determining the density of the multiphase mixture, the mass flow rate by change of momentum and the proportion of water and oil by measuring the dielectric properties of a separated flow stream of liquid, or by measuring the pressure differential of identical height columns of a water-oil mixture and water alone, respectively.
2. Background
In the production of hydrocarbon fluids from subterranean wells, it is common to be required to handle a multiphase fluid mixture comprising primarily crude oil, water and gas. For various reasons it is important to be able to determine the mass flow rate of each component of such a mixture from each well or from a selected number of wells which deliver their production into a common manifold or flowline.
Conventional apparatus for measuring the flow of fluids produced from oil wells requires separation of the components and measurements by conventional single phase fluid measuring devices. This type of equipment takes up a considerable amount of space, is expensive and is not usually suitable for continuously monitoring the fluid produced from a well or a selected number of wells. Accordingly, it has been considered highly desirable to provide a multiphase mass flow meter that does not require substantial separation processes, is compact enough to be considered for installation on offshore production platforms and the like, and can essentially be interposed in the main fluid flowline through which the produced fluids are conducted. Since it would be desirable also to provide such a mass flow measuring system on each well flowline or a well flowline from a selected number of wells, the cost of such a system must also be given serious consideration.